class_docstr: `dict`-like object which acts as if the value for any key is the key itself. Objects
  of this class can be passed in to arguments like `color_discrete_map` to
  use the provided data values as colors, rather than mapping them to colors cycled
  from `color_discrete_sequence`. This works for any `_map` argument to Plotly Express
  functions, such as `line_dash_map` and `symbol_map`.
code: def copy(self):
      return self
  
file_path: catboost/contrib/python/plotly/py2/plotly/express/_special_inputs.py
label_desc: Use image node_id 3 for calling the IdentityMap obj's underlying member method code with example usage: obj.copy() and returns: self